WO2003106975A1

WO2003106975A1 - Gas detection device

Info

Publication number: WO2003106975A1
Application number: PCT/JP2003/006472
Authority: WO
Inventors: 井本　努
Original assignee: ソニー株式会社
Priority date: 2002-05-28
Filing date: 2003-05-23
Publication date: 2003-12-24
Also published as: JP3912317B2; JP2004053582A; AU2003242433A1; US20050252273A1; US7216527B2

Abstract

A gas detection device capable of accurately measuring specific components (odor, etc.) contained in measured ambient gas, and easily formable in a mobile type due to a compactness or allowed to be reduced in size with low noise, wherein a zero gas cylinder (9) as zero gas supply means and the other component parts are disposed in a casing (2), and test gas obtained by leading ambient gas on the outside of the casing (2) through pipes (12a) and zero gas fed from the zero gas cylinder (9) are alternately led into a sensor part (7) using a syringe (3) as a gas suction and exhaust means, the test gas is measured, and the operations of these parts are controlled by a data processing device (11), whereby the test gas can be accurately measured by comparing the measured results of the test gas with each other for each measurement, the test gas can be measured at a measured site by moving the gas detection device (1) there, the suction and exhaust amounts of these gases can be kept constant by a cylinder mechanism with less noise, and the device can be formed compact.

Description

Item ^: Gas detector Technical field

The present invention relates to a portable gas detection device capable of detecting a specific component in an atmosphere to identify, for example, an odor. Background art

FIG. 14 is a configuration diagram of a conventional odor discriminating device 31. As shown in FIG. In FIG. 14, gas from the outside world is taken in from the intake port 36, is sent to the exhaust port 37 by the pump 33 through the sensor 34 installed in the path of the pipe 38, and is also discharged. And returned to the atmosphere. At this time, an electric signal corresponding to the type and concentration of the odor contained in the introduced gas is extracted from the sensor 34, and the data processing device 35 identifies the odor and measures the concentration.

FIG. 15 is a schematic external view of a conventional odor discriminating device 31 configured as described above. Inside the main body 32, the sensor 34, the data processing device 35, the pump 33, etc. in FIG. 14 are built, and the intake port 36 at the tip of the sample probe protruding from the main body 32 is connected. Through the sensor, the surrounding gas taken as zero gas (reference gas) 4 2 and the test gas (inspection gas) 43 contained in the test gas container 44 are taken into the sensor 34 alternately to detect the odor in the test gas. The type and concentration are measured.

However, as the measurement is repeated, the odor component adheres to the sensor 34, and the zero level of the sensor 34 gradually changes from the initial state, making it impossible to perform an accurate measurement. 3 4 zero The bell is adjusted. The operation of the odor identification device is performed by operating the measurement start button 41, and the measured value is displayed on the meter 40.

By the way, the conventional odor discriminating apparatus 31 analyzes odors by detecting physical changes or chemical changes that occur when odor constituent molecules are adsorbed on the sensor material.

For example, in a crystal vibration sensor (QCM), different types of adsorbents are applied to the surface of a crystal oscillator, and the mass change that occurs when odor molecules are adsorbed to the adsorbent is determined by the change in the frequency of the crystal oscillator. Since the types of chemical substances that can be easily adsorbed differ depending on the nature of the odor molecules, for example, the polarity, the odor can be measured by measuring how much mass change has occurred in which adsorbent. It is possible to estimate the types and amounts of the constituent odor molecules.

Adsorption of odor molecules can be detected not only as a change in mass but also as a change in electrical resistance or a change in light absorption wavelength, and various sensors using such a method have been proposed. For example, sensors that use a change in electric resistance when odor molecules are adsorbed to a conductive polymer or a composite material in which conductive particles are dispersed in an insulating polymer have been put into practical use.

However, in a sensor material that adsorbs odor molecules, odor molecules remain on the surface of the sensor—or highly active molecules contained in the gas combine with the sensor material to alter the sensor material. Is inevitable.

In such a sensor, the sensor characteristics change depending on the usage history. Therefore, to identify the odor, it is necessary to use a sensor signal (vibration frequency for a crystal oscillator type, electrical resistance value for a cheoresistor type, or optical type). For example, relative change is mainly used instead of the absolute value of light absorption wavelength. Since such a relative change is measured as a signal intensity difference between a reference gas (zero gas) containing no odor and a test gas (test gas) containing the odor to be measured, For odor identification, it is necessary to measure both the zero gas and the test gas signals.

Therefore, in the case of the odor discriminator 31 shown in Fig. 15, first measure the outside air such as room air as zero gas, and then insert the inlet 36 into a container 44 such as a flask containing a sample. Then, the odor is identified by measuring the odor of the sample.

As described above, when the odor is identified by the odor identification device, it is necessary to measure both the test gas and the mouth gas, and the odor of the substance entering the container by the odor identification device 31 in FIG. 15 is determined. When identifying, the relative change in the sensor signal is obtained by inserting the inlet 36 into the container as the test gas and setting the inlet 36 out of the container as the zero gas. Can be measured, and the odor in the container can be identified.

However, when identifying odors that are widely drifting in the environment surrounding the odor identification device, there is a problem in that zero gas cannot be taken in from the surroundings, so that odors that are widely drifting around cannot be identified.

As this type of apparatus, Japanese Patent Application Laid-Open No. 9-250979 discloses an odor discriminating apparatus using a zero gas container. However, it is not intended to discriminate the odor of the atmosphere. Similarly, the test gas is also introduced from a container connected to the device, and is not intended to be carried to identify the smell of the atmosphere. In addition, the piping for switching between zero gas and test gas is complicated, and switching is cumbersome, so it seems difficult to construct a size suitable for carrying.

Also, Japanese Patent Application Laid-Open No. Hei 9-304424 discloses an odor discriminating apparatus that purifies the outside air and uses it as a zero gas so that the odor of the atmosphere can be discriminated. Although portability and odor identification in the atmosphere are being considered here, the measurement and purification of outside air are performed by switching valves, so The structure is complicated and switching is troublesome, so it seems difficult to construct a size that can be incorporated into a small household mouth pot.

Further, Japanese Patent Application Laid-Open No. 2000-155017 discloses an odor discriminating device using a zero gas container together, and qualitatively or quantitatively determines a sample gas based on a detection signal regarding the sample gas and a detection signal regarding the zero gas. However, since the zero gas container is not built-in, the suction and discharge of gas is performed by a pump, so the intake and discharge volume varies, which is accompanied by noise, and the purpose is to measure the smell of the atmosphere while carrying it. is not. In addition, the structure is complicated and it is necessary to switch the valve, so operability is lacking, and it is difficult to construct a portable size.

Some conventional odor discriminating devices use a fan-diaphragm pump to draw in gas. Because of their large external dimensions and high noise during operation, they are not necessarily suitable for use in portable or small pots that can be used in homes where quietness is required. .

Therefore, an object of the present invention is to accurately measure a specific component (smell, etc.) contained in the ambient gas to be measured, and to be compact and easy to be constructed in a mobile manner, or to have low noise and small size. An object of the present invention is to provide a gas detection device which can be used for gasification. Disclosure of the invention

That is, the present invention provides a gas detection device that alternately introduces a reference gas and a test gas into a sensor in a housing, and detects a specific component in the test gas. A supply source for the reference gas is provided therein, and the inspection gas is introduced from outside the housing. (Hereinafter referred to as a first gas detection device of the present invention).

According to the first gas detection device of the present invention, since the reference gas supply source is provided in the housing and the inspection gas is introduced from outside the housing, the surrounding gas in the region to be inspected is used as the inspection gas. Ambient gas can be measured by introducing it from outside the housing, and this test gas or reference gas is alternately introduced into the sensor built into the housing, and the measurement results of these gases are relatively measured for each measurement. In comparison, the measurement of the test gas can be performed more accurately.In this case, the reference gas is introduced from the reference gas supply source installed in the housing. Thus, the entire apparatus can be made compact, and the apparatus itself can be easily moved to a required place together with the reference gas supply source.

Further, the present invention provides a gas detection device for alternately introducing a reference gas and an inspection gas to a sensor in a housing, and detecting a specific component in the inspection gas, wherein a supply source of the reference gas to the sensor is provided. The detection gas is introduced from the outside of the housing, and the reference is obtained by reciprocating pistons of a cylinder mechanism composed of a combination of a piston and a cylinder that sucks or discharges gas by expanding or reducing the internal volume. The present invention relates to a gas detection device (hereinafter, referred to as a second gas detection device of the present invention) in which gas or the inspection gas is introduced into the sensor.

According to the second gas detection device of the present invention, the reference gas from the reference gas supply source or the inspection gas from outside the housing is introduced into the sensor 1 by the forward and backward movement of the piston of the cylinder mechanism. The ambient gas can be measured by introducing the surrounding gas from the outside of the housing as a gas, and the inspection gas and the reference gas from the reference gas supply source are alternately introduced into the sensor to measure these gases. Accurate measurement of test gas by comparing results relative to each other In addition, since these gases are sucked or exhausted by the reciprocating motion of the piston in the cylinder, the amount of gas suction and exhaust is quantified, and at the same time, a low-noise, compact gas detector is provided. Can be.

The present invention further provides a gas detection device that alternately introduces a reference gas and a test gas into a sensor and detects a component contained in the test gas, wherein the sensor and a supply source of the reference gas are integrated. The present invention also provides a gas detection device characterized by the following (hereinafter, referred to as a third gas detection device of the present invention).

According to the third gas detection device of the present invention, since the sensor and the supply source of the reference gas are integrated, the same effects as those of the first gas detection device of the present invention can be obtained, It can be configured to be portable (in particular, mountable on a movable mouth pot) integrally having the sensor and the reference gas supply source. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic configuration diagram of a gas detection device according to Embodiment 1 of the present invention.

FIG. 2 is a graph showing a principle diagram of a signal waveform detected according to the first embodiment.

FIG. 3 is a principle diagram showing a sensor structure and a function of the gas detection device according to the first embodiment.

4A to 4C are diagrams showing a structure of a sensor of the gas detection device.

5A to 5B are diagrams showing the configuration of the sensor unit of the gas detection device, FIG. 5A is a schematic diagram, and FIG. 5B is a line bb in FIG. 5A. It is sectional drawing. FIG. 6 is a measurement circuit diagram of the same sensor.

FIG. 7 is a graph showing a specific example of the measurement by the gas detection device, and FIG. 8 is a graph showing another specific example of the measurement by the gas detection device.

FIG. 9 is a schematic configuration diagram of the gas detection device according to the second embodiment, and FIG. 10 is a schematic configuration diagram of a modification example of the gas detection device according to the second embodiment.

FIG. 11 is a schematic diagram showing another example of the purifying device of the gas detection device according to the second embodiment.

FIG. 12 is a schematic view showing still another example of the gas detecting device purifying apparatus according to the second embodiment.

FIG. 13 is a schematic configuration diagram showing a modification of the gas detection device according to the first embodiment.

FIG. 14 is a schematic configuration diagram of a conventional gas detection device.

FIG. 15 is a schematic external view of the gas detector. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described.

In the first, second, and third gas detection devices of the present invention described above, it is determined that the case is portable, and that the inspection gas is the ambient gas outside the case. It is desirable because the gas around the place can be inspected.

In this case, it is desirable that the supply source of the reference gas is a container containing the reference gas, because it can be easily installed in the housing, and the entire apparatus can be configured to be compact and easily moved. In particular, the sensor and the supply source of the reference gas are included in, for example, a self-contained robot device that operates independently, and the sensor and the supply source of the reference gas are included in the same housing. Preferably, the inspection gas is supplied from around the robot device, for example, from outside the housing.

An intake / exhaust mechanism for inhaling or exhausting gas by increasing or decreasing the internal volume; a flow path of the reference gas or the inspection gas communicating with the intake / exhaust mechanism; The reference gas supply source for determining a zero level at the time of detection, the sensor for measuring the reference gas and the inspection gas, and processing of output data of the sensor and control of operation of each unit. A control unit for performing one of the operations is provided, and the inspection gas or the reference gas is supplied to the sensor by an intake or exhaust operation of the intake / exhaust mechanism, and the intensity of the measured signal causes the inspection gas or the reference gas to be included in the inspection gas. It is desirable to configure so that a specific component is identified.

Further, the reference gas or the inspection gas is introduced into the sensor by reciprocating motion of a piston of a cylinder mechanism composed of a combination of a piston and a cylinder. This is desirable in that the apparatus can be easily reduced in size.

In this case, a one-way valve that guides gas only in one direction from the sensor to the cylinder mechanism is used during gas suction, and a one-way valve that guides gas only in one direction from the cylinder mechanism to a discharge outlet is used during discharge. Preferably, the one-way valve for gas suction is connected between the sensor and both chambers of the cylinder mechanism partitioned by the piston.

That is, one side of the two chambers of the cylinder mechanism is connected to the sensor 1 and the exhaust port via the one-way valve, and the other side is connected to the sensor via the one-way valve, respectively. The one-way valve connected to the sensor and the exhaust port, and connecting the sensor and the cylinder mechanism, The one-way valve connecting the cylinder mechanism and the exhaust port opens and closes so that gas flows only from the cylinder mechanism to the cylinder mechanism, and the one-way valve opens and closes such that gas flows only from the cylinder mechanism to the exhaust port. Thus, the gas can be drawn into the sensor without interruption by one cylinder mechanism.

In this case, a first valve is provided between the sensor and the intake port for sucking the inspection gas from outside the housing to the inside thereof, and a second valve is provided between the reference gas supply source and the sensor. When the piston moves in one direction, the first valve opens and the test gas is taken into the sensor, and when the piston moves in the opposite direction, When the second valve is opened and the reference gas is drawn into the sensor, it is preferable that the reference gas and the test gas are alternately sent to the sensor by one cylinder mechanism without interruption. . Further, in this gas detection device, the supply source of the reference gas is a means for purifying the gas for detection, and after the gas for detection after detection is purified by the means for purifying, the gas is used as the reference gas. They may be reused. This is desirable in that a supply source for generating and supplying a reference gas without a reference gas storage container can be built in.

In the case where purification cannot be performed in one purification step by the purifying means, after the detection, the inspection gas is passed through the purifying means to be purified, and then passed through the purifying means again to be used as the reference gas. You may do so.

In this case, it is desirable to provide a container for temporarily storing the test gas passed through the purifying means, and to introduce the test gas from the container into the sensor again.

That is, when the inspection gas is sucked into the cylinder mechanism from the gas inlet, after being subjected to the detection by the sensor, the gas is supplied to the purification unit. It is further purified and temporarily stored in the cylinder mechanism, and when discharged from the cylinder mechanism, is passed again through the purification means to be purified to generate the reference gas, and the reference gas is introduced into the sensor. It is desirable to configure as follows.

Further, it is preferable that the purifying means is deodorizing or Z and dehydrating means, and that the introduced test gas is deodorized and / or dehydrated or converted into a reference gas by performing both.

As described above, as a reference gas supply source, a portable inspection gas is configured by being installed in a housing of a container containing the reference gas or in a housing of a purification device that generates the reference gas, It can be suitably used for odor identification. Next, preferred embodiments of the above-described first, second and third gas detectors will be specifically described with reference to the drawings.

Embodiment 1

This gas detector measures a specific component (smell) contained in a test gas (hereinafter sometimes referred to as a test gas), its amount, concentration, and the like. The difference between the basic configuration of the first and second gas detectors 1 ′ is that the first gas detector 1 has a reference gas (hereinafter sometimes referred to as “zero gas”) supply source installed in the housing. That is, the second gas detector 1 'specifies that a cylinder mechanism is provided as a gas intake / exhaust mechanism.

Therefore, in the following description (including other embodiments to be described later), the first and second gas detectors are common to both unless otherwise noted. In addition, the following drawings are also used for description as drawings common to both.

As shown in Fig. 1, the schematic configuration of the first gas detection device 1 is as follows: a cylinder 9 as a zero gas supply source, and a sensor unit for gas detection 7 and a data processing device 11 for controlling data processing and operation of each unit.

As a gas intake / exhaust mechanism, for example, a cylinder mechanism (syringe) 3 composed of a combination of a piston and a cylinder is provided inside, and by the operation of the cylinder mechanism 3, external air and a cylinder introduced as test gas from the intake port 14 are introduced. Zero gas from 9 through regulation 10 is supplied to sensor part 7 by opening and closing first and second pulp 8a and 8b through piping 12a or 12b. After the measurement, these gases are sucked into the cylinder mechanism 3 through the one-way valve 6a or 6b, and discharged through the one-way valve 6c or 6d. The operation of each unit is controlled by the data processing device 11. However, the syringe 3 as a gas suction / discharge mechanism may be an essential component. As a result, the first gas detector 1 measures the outside air widely drifting around the area introduced as the test gas and the zero gas supplied inside, and relatively compares the measurement results of the sensor one signal for each measurement. However, accurate measurement of the difference is always possible, so that it is possible to easily identify the odor of the environment. Therefore, it is not necessary to switch the valve as in the conventional example, so that the operability is good. The structure is simplified, and a small-sized odor discriminator suitable for carrying or embedding can be realized, and the device itself can be moved to a required place.

As shown in FIG. 1, a schematic configuration of the second gas detection device 1 ′ includes a sensor 7 for gas detection, a data processing and a data processing for controlling the operation of each part inside the housing 2. A device 11 and a cylinder mechanism (syringe) 3 composed of a combination of a piston and a cylinder are provided.

The zero gas is supplied from, for example, a zero gas cylinder 9 provided in the housing, and outside air is introduced from an intake port 14 as a test gas. Then, by the operation of the cylinder mechanism 3, the outside air introduced from the intake port 14 and the zero gas passing through the cylinder 10 from the cylinder 9 are supplied to the pipe 1. After passing through 2a or 12b, the first and second valves 8a and 8b are opened and closed to supply the sensor part 7 and measured, and the gas after measurement passes through the one-way valve 6a or 6b to the cylinder. It is sucked into the mechanism 3 and discharged through the one-way valve 6c or 6d. The operation of each unit is controlled by the data processing device 11. However, the internal configuration of the zero gas cylinder 9 as a zero gas supply source may be an essential configuration requirement.

As described above, the second gas detection device 1 ′ can reduce noise during operation by using a syringe (or a bellows pump) 3 instead of a conventional pump. Ambient gas is introduced from outside the housing 2. Zero gas and this gas are alternately introduced into the sensor, and the measurement results of these gases are relatively compared to each other for accurate measurement. In addition, there is no need to switch valves as in the past, and the simplified structure makes it easy to operate, and a small odor discriminator suitable for carrying or embedding is configured, and the device itself is moved to the place where measurement is desired. can do.

In FIG. 1, the sensor used may be the same as the conventional one. As a suction or exhaust means, a syringe 3 having an intake port and an exhaust port on both sides of the cylinder 4 is used, and a first valve 8a is provided between the intake port 14 and the sensor section 7, The second pulp 8b is also provided between the zero gas cylinder 9 and the sensor unit 7. The first valve 8a and the second valve 8b are valves that alternately switch between the zero gas from the zero gas cylinder 9 and the test gas from the intake port 14.The control signal 16 from the data processor 11 The opening and closing are controlled, so there is no need to switch valves.

The zero gas cylinder 9 is a container filled with dry air, nitrogen, etc., which can be replaced after the zero gas inside the container is exhausted, or can be refilled with the internal gas. It is. Regyuray 10 is used to adjust the zero gas pressure applied to the second valve 8b side. is there. In addition, the test gas can be separately collected at a place to be measured, packed in a container such as a cylinder, and connected to the intake port 14 to supply the test gas. Alternatively, the third gas detection device 1 (1 ′) operates, for example, in the following order.

step 1

Close the first valve 8a, open the second valve 8b, and move the piston 5 of the syringe 3 from left to right in the figure. At this time, the zero gas is introduced into the sensor section 7 from the cylinder 9 through the second valve 8b, and the zero point of the sensor signal 17 is measured. The gas on the right side of the piston 5 of the syringe 3 is exhausted to the outside through the exhaust port 15b.

Step 2

Open the first valve 8a, close the second valve 8b, and move the piston 5 of the syringe 3 from right to left in the figure. At this time, a test gas is introduced into the sensor part 7 from the intake port 14 through the first valve 8a, and a change in the rise of the sensor signal 17 is measured. The test gas introduced into the sensor unit 7 is directly taken into the volume on the right side of the piston 5 of the syringe 3. With the movement of piston 5, the gas on the left side is exhausted to the outside through the exhaust port 15a.

Step three

Close the first valve 8a, open the second valve 8b, and move the piston 5 of the syringe 3 from left to right in the figure. At this time, zero gas is introduced from the cylinder 9 through the second valve 8b into the sensor unit 7, and the change of the falling edge of the sensor signal 17 is measured. The gas on the right side of the piston 5 of the syringe 3 is discharged to the outside through the exhaust port 15b. By the above operation, for example, a signal waveform as shown in FIG. 2 can be observed. By taking this waveform into a data processor and analyzing it, the smell of the test gas can be accurately identified.

FIG. 2 is a principle diagram of odor identification by the gas detection device, and shows signal waveforms of sensors 30a, 30b, and 30c arranged in the sensor unit 7 for detecting different gas components. . That is, for each zero level of the sensor signal 17 measured by the zero gas inhaled in Step 1, each sensor 30a, 30b, The change in electrical resistance of 30 c is measured as signal waveforms A, B, and C. Therefore, by taking this waveform into the data processing device 11 and analyzing it, it is possible to identify the color.

FIG. 3 shows a principle diagram of a sensor structure for odor discrimination in such sensors 30a, 30b, and 30c.

That is, in this sensor 30 ′, for example, electrodes 46 are provided on both sides of a polymer 45 in which carbon black is dispersed, and the polymer 45 is exposed to gas introduced into one chamber. As a result, the odor component adheres to the polymer 45 and swells to change the electric resistance.The change in the electric resistance is measured by a measuring circuit via wiring, and the result is a signal waveform as shown in FIG. Is measured as

Next, the structure and function of the sensor in the sensor part 7 in the gas detection device 1 (1 ′) according to the present embodiment will be described with reference to specific examples shown in FIGS. 4A to 8.

As shown in FIG. 4A, the sensor 30 is provided with electrodes 26 at both ends on a glass substrate (for example, about 300 xm thick) 25 and excluding the upper surface of the electrode 26 This is a structure in which a sensor material thin film 28 is provided on the entire surface. This glass substrate 25 is a support material for the sensor material thin film 28 and the electrode 26, The material may be a silicon substrate or a plastic substrate having an oxide film formed on the surface. The electrode 26 is an electrical contact between the sensor material thin film 28 and the external wiring. For example, a deposited film of Ti (titanium) / Au (gold) = 50 nm / 200 nm is lifted off. Patterned.

The sensor-material thin film 28 is a thin film whose electrical resistance changes when a certain type of odor molecule is adsorbed, as shown in Figs. 4B and 4C as an enlarged cross-sectional view of part b in Fig. 4A. In addition, a metal thin film 49 (for example, Au particles having a diameter of about φ = 4ηπι) is a thin film having a laminated structure in which the linker molecules 50 are bonded to each other. An organic molecule having a functional group that forms a coordination bond with the metal fine particles 49 (for example, _SH group for Au particles), such as l, 9-nonanedithiol (nonandithiol) or Biphenyl dithiol (biphenyl dithiol) is used.

FIG. 5A is a schematic cross-sectional view of a sensor part 7 containing the sensor 30 as described above, and FIG. 5B is a cross-sectional view taken along the line bb of FIG. 5A.

As shown in FIG. 5B, for example, three types of sensors 30a, 30b, and 30c are arranged in the sensor unit 7, and these sensors 30a, 30b30c are It is housed in an airtight sensor-chamber 27 (for example, made of Teflon (registered trademark)). The number of types of the sensor 130 may be one or more.

The stored sensors 30a, 30b, and 30c are used until the gas introduced from the intake port 47 provided in the sensor chamber 27 is exhausted from the exhaust port 48 force. In addition, it is exposed to the introduced gas and changes its electrical resistance. The change in the electric resistance of each sensor is measured by a sensor-measurement circuit through electric wires 29 connected to the sensors 30a, 30b, and 30c. Figure 6 is a diagram showing a measurement circuit of each sensor-and have use of this circuit, the partial pressure V. the reference resistance R _u _{The UT} may be measured to determine the relative change. In this case, V. _UT has the following relationship with _RD .

OUT ⁼ DD X where V _DD ,

That is, V. Measuring _UT gives the relative change in _RD . When this circuit is used, the measurement voltage is within the specified range (0 to V _DD ) regardless of the resistance value of the sensor, so there is no need to switch the measurement range, thus simplifying the voltage measurement circuit. There is an advantage that can be made.

The reference resistance Ru is preferably adjusted such that its resistance is approximately equal to the resistance _RD of the respective sensor. At this time, the maximum voltage sensitivity is obtained. The voltage V _DD is a fixed voltage for generating the V _{QUT. The} voltage V _DD is determined in consideration of the withstand voltage and life of the sensor, the measurement accuracy of the V _QUT , noise, and the like (for example, 50 to 200 mV). ).

7 and 8 are examples of measurement by the gas detection device 1 of the present embodiment, and show actual measurement graphs of signal waveforms by this measurement. For example, FIG. 7 shows coffee beans, and FIG. 8 shows whiskey. These are measurement examples, all of which are measurement results of signal waveforms measured with the same sensor array.

As described above, sensor part 7 is composed of three different types of sensors 30a.30b and 30c, so that the response waveform and signal amplitude of each sensor are Now you can see that they are different. Thus, it is possible to distinguish between coffee and whiskey from the difference in signal patterns. In these sensors, since the components that react more strongly differ from sensor to sensor, for example, a sensor that reacts more strongly with hydrophilic molecules or a sensor that reacts more strongly with hydrophobic molecules is installed. The performance of the sensors that make up the sensor array can be changed according to the composition of the odor components that are considered to be contained in the object.

The height of the measured waveform of each sensor decreases with time, and a change in the amplitude of the waveform is observed (each sensor in FIGS. 7 and 8). Also, a shift in the zero-level position of each sensor is observed (for example, sensors 30a and 30c in FIG. 7 have a reduced zero-level position and 3Ob has increased). This phenomenon is because the function of the sensor decreases due to the adhesion of the smell molecules of coffee beans and whiskey and the hydrophilic molecules, which are considered to be contained in coffee beans and whiskey, to the surface of the sensor material. Therefore, by introducing the zero gas and the test gas alternately into a part of the sensor, the signal level difference between the zero gas and the test gas can be measured as a relative change while the zero level of the sensor is adjusted.

As described above, by using the gas detection device of the present embodiment, it is possible to measure the gas at the place to be measured, and to determine the type and amount of the specific component contained in the surrounding atmosphere of the object. Concentration can be measured easily and accurately.

According to the present embodiment, in the first gas detection device 1, a cylinder 9 containing a vent gas as a reference gas is provided in the housing 2, and ambient gas is introduced from the intake port 14 as a test gas. These gases are alternately introduced into the sensor — and the measurement results are compared relatively for each measurement to enable accurate measurement of phrases in the surrounding gas, as well as operability. Move the gas detector 1 to the place where you want to measure and measure it on site In addition, when the test gas is supplied from a separately collected container, the measurement can be performed with this device fixed at a place other than the site. Further, it is possible to install a syringe 3 in the housing 2 for gas inhalation and exhaustion, whereby quantification of the gas intake and exhaust volumes and low noise operation can be performed.

In addition, the second gas detector 1 ′ can measure by introducing a surrounding gas outside the housing as a test gas.The test gas and the zero gas are alternately introduced into the sensor, and the measurement result is obtained. Accurate measurement of test gas length can be made by comparing each measurement relatively. In addition, since the intake and discharge of these gases are performed by the syringe 3, the amount of intake and exhaust of the gas can be quantified, and the operation can be performed with low noise. Further, the operability of the apparatus is good, and it is also possible to install a zero gas cylinder 9 in the housing as a zero gas supply source. The test gas can be moved and measured on the spot, or it can be measured at another location by sampling and supplying only the test gas.

Embodiment 2

Figure 9 is, _t the gas detection device 1 A showing a schematic configuration of a gas detection device 1 A according to this embodiment, as in the first embodiment described above, Tesutoga scan capture the ambient gas in the housing However, the first embodiment differs from the first embodiment in the reference gas supply source, the cylinder mechanism, and the pipes and valves associated therewith. It functions in the same way as the first and second gas detectors. Such a configuration can be applied to the above-described first or second gas detection device. The gas intake / exhaust mechanism includes a cylinder 4a and a piston 5a that inhale or exhaust from the same side. Syringe 21 is installed inside housing 2 and As a reference gas supply source, a used test gas is purified by a purifier 19 to be converted into a reference gas.

That is, the outside air introduced from the intake / exhaust port 23 through the pipe 12 a is purified by the purifier 19 after the data on the test gas is measured by the sensor part 7, and the cylinder of the syringe 21 is The gas is once contained in 4a, and when this gas is discharged, the gas is purified again by the purifier 19 to be a reference gas, and this gas is supplied to the sensor unit 7 as a reference gas. Therefore, the test gas and the reference gas are alternately introduced into the sensor part 7 and the measurement results of the gas in the sensor part 7 are relatively compared for each measurement. The intake / exhaust mechanism consisting of 1 quantifies the amount of gas intake and exhaust, making it possible to construct a portable, low-noise, compact gas detector. However, in this case as well, the test gas is supplied in a sampled manner, and the measurement can be performed with the device fixed.

As described above, the gas detection device 1A according to the present embodiment purifies and reuses the test gas subjected to the odor measurement as the zero gas, thereby making the components such as valves necessary for switching to the zero gas. The structure can be simplified by reducing the size, and a small-sized odor discriminator suitable for carrying or incorporating can be obtained.

Also in the present embodiment, the same sensor as in the related art can be used. The purifying device 19 is a device that removes moisture and odor molecules in the test gas.For example, it is a filtration device that is configured so that the gas passes through individual containers containing silica gel, activated carbon, and various catalysts in order. is there. The syringe 21 includes a cylinder 4a, a piston 5a, and a driving device for a piston. The piston 5a reciprocates according to a control signal 18 from the data processing device 11. Therefore, there is no need to switch valves. First, when the piston 5a draws in the test gas, environmental gas is taken in from the intake / exhaust port 23 and sent to the sensor unit 7. The test gas sent to the sensor section 7 causes a change in the sensor signal 17 characteristic of the test gas, and this data is measured by the data processing device 11. It is sent to 9 to remove odor molecules and water contained in the gas. The gas thus purified is temporarily taken into the syringe 4a of the syringe 21.

Next, the piston 5a pushes out the purified gas taken into the syringe 21. At this time, the purified gas taken in the cylinder 4a is sent to the sensor part 7 again through the purification device 19. At this time, the gas sent to the sensor part 7 is zero gas due to the two purifications.By comparing the response of the sensor part 7 to the zero gas and the response to the test gas, the characteristic of the test gas is obtained. It is possible to obtain a unique signal pattern and to accurately identify the test gas.

Since the gas detector 1A generates zero gas internally by purifying the test gas, accurate identification is possible even for test gases that are widely distributed in the environment surrounding the gas detector 1A. is there.

FIG. 10 is a schematic configuration diagram of a gas detection device 1B according to a modification of the second embodiment.

That is, the purifying device 20 can increase the purifying ability by the material and the internal structure to be contained, and can generate zero gas as a reference gas by one filtration. Therefore, a purifying device 20 having high purifying performance is provided, and the necessary piping 12b and valves 8a and 8b are provided in a configuration different from that of FIG. This device can be applied to the above-described first and second gas detection devices, similarly to the device shown in FIG. Since this gas detector 1B can generate the reference gas by one-time filtration by the purifier 20, the valve 8a is opened when the syringe 21 is inhaled, the valve 8b is closed, and the gas is inhaled. The test gas passes through the sensor unit 7 and the purifying device 20, and the generated reference gas is temporarily stored in the cylinder 4a of the syringe 21, and at the time of discharge, the valve 8a is closed and the valve 8b is opened. The reference gas is supplied to the sensor unit 7 via the pipe 12b.

FIGS. 11 and 12 are diagrams showing other examples of the filtering structure of the purifying device 20 in the gas detection device 1B. For example, as shown in FIG. , 20b and 20c, in which a plurality of purifying devices are arranged in parallel. FIG. 12 shows a structure (for example, 20 c may be added) in which purifiers 20 a 20 b similar to those described above are arranged in series. I can show my ability.

According to the present embodiment, as a test gas, the gas around the housing 2 can be introduced and its odor can be measured, and the purifier 19 (or 20) is provided inside the housing 2. Since the reference gas is generated internally by purifying the test gas introduced from the outside, the test gas and the reference gas are alternately introduced into the sensor so that accurate measurement can be performed. If the test device is supplied from a cylinder with the discharge device 1 A (or 1 B) and can be measured on site, this device can be fixed and measured at a location other than the site. .

In each of the above examples, a syringe was used as the intake / exhaust means, but these may be replaced with a bellows pump. The bellows pump can achieve the same low noise and compactness as a syringe.

FIG. 13 is a schematic configuration diagram showing a gas detector 1C according to a modification of the first embodiment. As in the first embodiment, the gas detector 1C can be applied to the first and second gas detectors. it can. That is, as shown in FIG. 13, this gas detection device 1C is provided with a pump similar to the conventional example as a gas intake / exhaust means. Other than this, the configuration is the same as that of the first embodiment, and by handling it in the same manner as the first embodiment, sufficient performance can be exhibited and the device can be formed in a portable manner. It can be taken to the site where it is to be used for on-site measurement, while the test gas can be supplied from a cylinder to fix this device to a location other than the site for measurement.

According to each of the above-described embodiments, the zero gas is generated inside the housing or inside the housing by the purifying device, so that the odor identification can be performed anywhere without restriction on the measurement place. The smell of the environment surrounding the device can be identified.

Therefore, for example, when this device is installed in a mouth pot, the mouth pot analyzes the smell around it, and detects fires in a separate room of a house or a neighborhood, the state of cooking, the return of a family member, illegal invasion, etc. It is also possible to analyze the odor of the environment by taking this device to streets, forests, and the seaside.

Furthermore, by using a syringe or a bellows pump as the intake / exhaust mechanism, noise generated by the intake / exhaust operation is reduced, and a small-sized odor discriminating device suitable for carrying or assembling can be realized.

In addition, by purifying and accumulating the test gas used for measurement by the sensor and reusing it as a zero gas, it is possible to reduce parts such as valves required for switching between the zero gas and the test gas, and to further improve the entire device. It can be downsized.

Each of the above embodiments can be modified based on the technical idea of the present invention. For example, a test gas can be measured by bringing the device to the site to measure the environmental gas at the place where the measurement is to be performed, and then inhaling the test gas at the place, but measuring only the test gas. The sample can be separately collected in a container such as a cylinder, and the device can be fixed at another place for measurement.

Further, the first gas detection device is limited to the inside of the zero gas cylinder, and the gas suction / discharge mechanism may be a syringe.The second gas detection device may be limited to the gas suction / discharge mechanism with a syringe. Although the zero gas may be provided inside the zero gas cylinder, both the first and second gas detectors may use the zero gas cylinder and the syringe together.

In addition, as the gas intake / exhaust means, an intake / exhaust means using a piezoelectric element or other intake / exhaust means other than the above-described syringe, pump or port-and-mouth pump can be used.

Although the embodiment has been described for identification of odors in a test gas, the present invention can also be applied to, for example, measurement of the type, quantity, concentration, and physical properties of a gas.

Further, the structure, arrangement, and the like of each unit of the device described in the embodiment can be appropriately implemented in addition to the embodiment. The above-described gas detection device can be incorporated in a independently driven ropot device.

As described above, according to the first and third gas detectors of the present invention, the reference gas supply source is provided inside the housing, the inspection gas is introduced from outside the housing, or the reference gas supply source Since the sensor and the sensor are integrated, the surrounding gas in the area to be inspected can be introduced as a test gas from the outside of the housing to measure the surrounding gas. The test gas can be accurately measured by alternately introducing the sensor into the sensor built into the body, and comparing the measurement results of these gases with each other for each measurement. Since the gas is introduced from the internal reference gas supply source, the reference gas supply The entire apparatus can be made compact as compared with the case where the apparatus is provided, and it is easy to move the apparatus itself to a required place together with the reference gas supply source.

According to the second gas detection device of the present invention, the reference gas from the reference gas supply source or the inspection gas from outside the housing is introduced into the sensor 1 by the reciprocating movement of the piston of the cylinder mechanism. Ambient gas can be measured from the outside of the enclosure as an inspection gas to measure the ambient gas.The inspection gas and the reference gas from the reference gas supply source are alternately introduced into the sensor to measure these gases. Inspection gases can be measured accurately by comparing the results relative to each measurement, and these gases are sucked or exhausted by the reciprocating motion of the piston in the cylinder. In addition, it is possible to provide a low-noise, compact gas detector.

Claims

The scope of the claims

1. In a gas detection device for introducing a reference gas and a test gas alternately into a sensor in a housing to detect a specific component in the test gas, the gas detection device includes: A gas detection device, wherein a reference gas supply source is provided inside, and the inspection gas is introduced from outside the housing.

2. The gas detection according to claim 1, wherein the housing is portable.

3. The gas detection device according to claim 1, wherein the inspection gas is a surrounding gas outside the housing.

4. The gas detection device according to claim 1, wherein the supply source of the reference gas is a container containing the reference gas.

5. The supply source of the reference gas is a purifying means for the inspection gas, and the inspection gas after the detection is purified by the purifying means, and then is reused as the reference gas. Gas detection device described in paragraph 1.

6. The gas detection device according to claim 5, wherein, after the detection, the inspection gas is passed through the purification unit to be purified, and then passed through the purification unit again to be used as the reference gas.

7. The container according to claim 5, further comprising a container for temporarily storing the test gas passed through the purifying means, wherein the test gas is introduced again into the sensor from the container. The gas detector described in the paragraph.

8. The gas detection device according to claim 5, wherein the purification means is a deodorizing or Z and dehydrating means.

9. Intake / exhaust mechanism that inhales or exhausts gas by increasing or decreasing the internal volume, the flow path of the reference gas or the inspection gas that communicates with the intake / exhaust mechanism, and the time of the detection of the inspection gas At least one of the reference gas supply source for determining the zero level of the sensor, the sensor for measuring the reference gas and the test gas, and processing of output data of the sensor and control of operation of each unit. A control unit for performing the above operation, wherein the test gas or the reference gas is supplied to the sensor by the suction or discharge operation of the suction / exhaust mechanism, and a specific component in the test gas is determined based on a measured signal intensity. The gas detection device according to claim 1, wherein is identified.

10. The gas detection device according to claim 9, wherein the reference gas or the inspection gas is introduced into the sensor by reciprocating a piston of a cylinder mechanism including a combination of a piston and a cylinder.

1 1. A one-way valve that guides gas from the sensor to the cylinder mechanism only in one direction during gas suction is used, and a one-way valve that guides gas only from the cylinder mechanism to the discharge port is used during discharge. The gas detection device according to claim 10, wherein:

12. The claim according to claim 11, wherein the one-way valve for gas suction is connected between the sensor and both chambers of the cylinder mechanism partitioned by the piston. Gas detector.

13. One side of each of the two chambers of the cylinder mechanism is connected to the sensor 1 and the exhaust port via the one-way valve, and the other side is respectively connected to the one-way valve via the one-way valve. The one-way valve, which is connected to the sensor and the exhaust port and connects the sensor and the cylinder mechanism, opens and closes so that gas flows only from the sensor to the cylinder mechanism. The one-way valve that connects the mechanism and the exhaust port opens and closes so that gas flows only from the cylinder mechanism to the exhaust port, so that one cylinder The gas detection device according to claim 12, wherein a mechanism is configured to draw a gas into the sensor without interruption.

14. An intake port for sucking the test gas from the outside of the housing into the inside thereof. A first valve is provided between the sensor and the sensor, and between the reference gas supply source and the sensor. A second valve, wherein when the piston moves in one direction, the first valve opens and the test gas is taken into the sensor, and the piston moves in the opposite direction; In this case, the second valve is opened and the reference gas is drawn into the sensor 1 so that the reference gas and the test gas are alternately sent to the sensor 1 without interruption by one cylinder mechanism. The gas detection device according to claim 13.

15. The gas detection device according to claim 9, comprising the purifying means according to claim 5.

16. The gas detection device according to claim 15, comprising the purifying means according to claim 6.

17. When the inspection gas is sucked into the cylinder mechanism from the gas inlet, after being subjected to the detection by the sensor, the gas is purified by the purification means and stored in the cylinder mechanism. The gas detection according to claim 15 or 16, wherein the reference gas is passed through the purification means and purified again to generate the reference gas. apparatus.

18. The gas detection device according to claim 1, wherein the gas detection device is used for identifying an odor of the inspection gas. ·

1 9. In a gas detection device that alternately introduces a reference gas and an inspection gas into a sensor in a housing and detects a specific component in the inspection gas, the supply source of the reference gas is provided to the sensor. Connected, the inspection from outside the enclosure The reference gas or the test gas is supplied to the sensor by the reciprocating movement of the piston of a cylinder mechanism composed of a combination of a piston and a cylinder, which introduces a test gas and sucks or discharges the gas by increasing or decreasing the internal volume. Introduced into the gas detector.

20. A flow path of the reference gas or the test gas communicating with the cylinder mechanism, the reference gas supply source for determining a zero level of the test gas at the time of the detection, the reference gas and The sensor for measuring the test gas; and a control unit for performing at least one of processing of output data of the sensor and control of operation of each unit. 10. The gas detection device according to claim 19, wherein the reference gas is provided to the sensor, and a specific component in the test gas is identified based on a measured signal intensity.

21. A one-way valve that guides gas from the sensor to the cylinder mechanism only in one direction during gas suction is used, and a one-way valve that guides gas from the cylinder mechanism to the outlet only in one direction is used during discharge. The gas detector according to claim 19, wherein

22. The range of claim 21 wherein the one-way valve for gas suction is connected between the sensor 1 and both chambers of the cylinder mechanism separated by the piston. Gas detector.

23. One side of each of the two chambers of the cylinder mechanism is connected to the sensor and the exhaust port via the one-way valve, and the other side is respectively connected to the one-way valve via the one-way valve. The one-way valve, which is connected to the sensor and the exhaust port and connects the sensor and the cylinder mechanism, opens and closes so that gas flows only from the sensor to the cylinder mechanism. The one-way valve that connects the mechanism and the exhaust port opens and closes so that gas flows only from the cylinder mechanism to the exhaust port, so that one cylinder The gas detection device according to claim 22, wherein a gas is continuously drawn into the sensor by a mechanism.

24. A first valve is provided between the inlet and the sensor for sucking the inspection gas from outside the housing to the inside thereof, and a first valve is provided between the reference gas supply source and the sensor. With two valves, the piston moves in one direction,

When the first valve is opened and the test gas is taken into the sensor, and when the piston moves in the opposite direction, the second valve is opened and the reference gas is drawn into the sensor. 24. The gas detection device according to claim 23, wherein the reference gas and the inspection gas are alternately sent to the sensor by a single cylinder mechanism without interruption.

25. The gas detection device according to claim 19, comprising the purification means according to claim 5.

26. The gas detection device according to claim 25, comprising the purification means according to claim 6.

27. When the inspection gas is sucked into the cylinder mechanism from the gas inlet, after being subjected to the detection by the sensor 1, the gas is purified by the purification means and stored in the cylinder mechanism. The gas detection according to claim 25 or 26, wherein upon discharge from the mechanism, said reference gas is again passed through said purifying means and purified to generate said reference gas. This reference gas is introduced into said sensor. apparatus.

28. The gas detection device according to claim 25 or 26, wherein said purification means is deodorization or Z and dehydration means.

29. The gas detection device according to claim 19, wherein a supply source of the reference gas is provided in the housing, and the housing is portable.

30. The gas detection device according to claim 19, wherein the inspection gas is a surrounding gas outside the housing.

31. The gas detection device according to claim 19, wherein the reference gas supply source is a container containing the reference gas.

32. The gas detection device according to claim 19, wherein the gas detection device is used for identifying an odor of the inspection gas.

33. In a gas detection device that alternately introduces a reference gas and a test gas into a sensor and detects a component contained in the test gas, the sensor and the supply source of the reference gas are integrated. A gas detection device.

34. The gas detection device according to claim 33, wherein the sensor and the reference gas supply source are included in a robot device.

35. The gas detection device according to claim 34, wherein the robot device is a self-supporting robot device that is driven independently.

36. The gas detector according to claim 34, wherein the inspection gas is supplied from around the mouth pot device.

37. The gas detection device according to claim 33, wherein the sensor and the supply source of the reference gas are contained in the same housing.

38. The gas detection device according to claim 37, wherein the inspection gas is supplied from outside the housing.